no audio for a few seconds between clients

[Jor3cx]

I have a problem with 3cx on premiss (windows v15.5).

In an internal call between 2 devices, there is no audio in the first 2 seconds of the call. After the first 2 seconds the conversation goes well. This is with 2 ios phones, or with 1 ios phone and one yealink at an external location.

If I do the echo test with * 777 I do not hear any delay. I use direct sip (stun-remote). The firewall test has passed.

Does anyone have an idea?

 

[YiannisH_3CX]

Hello @Jor3cx

Since the common factor of the issue seems to be the IOS clients you should start from there.
Have you noticed the delay if the clients are on premise connected to the local network or is the delay present only when using 3g/4g
Are you using the latest clients? Have you tried an Android client to see if you replicate this behaviour?

 

[Jor3cx]

If the clients are on premise connected to the local network i also have the same problem. I am using te latest clients for iphone. I also tried it with android and also have a few seconds delay. Sometimes its 1 second sometimes a bit more.

 

[YiannisH_3CX]

Please note that 1-2 seconds delay is normal for a call established on the client. Once you accept the call the client has to send a 200 OK message to establish the call and negotiate the codecs that will be used before the RTP starts. Then the client has to start the audio device of the phone where the delay is. If you were using a Bluetooth audio device which is slower the delay would be more noticeable. This also relies on network speed and traffic. So a couple of seconds of delay is normal and is to be expected.

 

[Jor3cx]

ok, thanx for your reply.